Ratchet wrench



A. U. KERNS RATCHET WRENCH Sept. 12, 1933.

Filed Sept. 28, 1932 ITNESSES; @fimz). 15

I N VEN TOR: Hal/m Uifw'ns, BY W A TTORN E Y5 Patented Sept. 12, 1933 oNrrsn terrain RATCHE'E WRENH Adin U. Kerns, Altoona, Pa.

Application September 28, 1932 Serial No. 635,171

2 Claims.

My invention relates to ratchet wrenches, and more particularly to a double-acting ratchet wrench having a socket adapted to be applied to a nut or like part to be turned. By a double- 5 acting wrench I mean a wrench which, when it is set in one position, and the'handle is moved back and forth, will cause the part to which it is applied to be turned in one direction and which when set in another position, and the handle is similarly moved back and forth, will cause the part to which it is applied to be turned in the other direction. The ratchet wrench oi this invention is also adapted to be set in a neutral position in which case the handle of the tool will turn freely in either direction about the part to which it is applied.

The principal object of the invention is to provide a double-acting ratchet wrench which may be conveniently operated with all of its functions controlled by a movement of one hand, while that hand retains a firm grip on the tool. Accordingly, the ratchet wrench of this invention is particularly useful where the operator has only one hand available to work the wrench. An example of the use to which the ratchet wrench of this invention is particularly adapted will be found in my pending application for U. S. Letters Patent Serial No. 635,170, filed September 28, 1932, wherein I have shown a riveting machine adapted for use on overhead catenary construction of electrified railways. In operating such a machine, the operator has one hand engaged on a stationary part of the machine, to hold the machine steady, and another hand available for operating the ratchet wrench. It is most desirable that he retain his grip on the ratchet wrench at all times. This object I accomplish by controlling the action of the ratchet wrench through turning of the handle about its own axis.

Other more specific objects and advantages characteristic of my invention will become apparent from the description of one embodiment or example thereof which follows hereinafter, having reference to the accompanying drawing. Of the drawing:

Fig. I represents an end elevation of a ratchet wrench of my invention.

Fig. II represents a side elevation of the same, with the head shown in cross section, taken as indicated by the lines IIII of Fig. I; and,

Fig. III represents a cross section of the tool handle, taken as indicated by the lines IIIIII of Fig. II.

With reference to the drawing, there is shown a ratchet wrench comprising generally a long (Cl. ill-63) tubular handle 1 and a bifurcated head 2. Mounted rotatably in the forks 3 of the head 2, there is a ratchet wheel 4 having a polygonal socket 5, which in the present instance is shown adapted to fit a hexagonal nut. The ratchet 60 wheel 4 has thereon a series of teeth 6 alternating with recessed areas 7, each tooth being formed with surfaces symmetrically disposed with reference to a radius line drawn from the center of the socket 5 through the center of the tooth.

Adjacent to the ratchet wheel i, there is pivotally mounted on a pin 8, a double-acting pawl 9 having one tooth 10a adapted to engage the teeth of the ratchet wheel 6 at one side of the tool head 2, and having another tooth 10b adapted 70 to engage the teeth of the ratchet wheel 6 at the other side of the tool head 2. At the opposite end of the pawl 9 there is a curved cam surface 11 which is adapted to be engaged by a pawl actuating member 12. The tubular handle 1 is at- 5 tached by a rivet 13 to a solid cylindrical shaft 14. The shaft 14 terminates in a shoulder 15 which engages in a correspondingly shaped opening in the sleeve portion 16 of the tool head 2. Accord-- ingly, the handle 1 and shaft 1 1 may rotate about their common longitudinal axis relatively to the tool head 2. At the end of the shaft 1 1 there is a diagonal slot 17 in which a spring 18 and the pawl actuating pin 12 are housed. The pawl actuating pin 12 which obviously may assume a variety of different forms or shapes is held within the slot 17 by a key 19. In an obvious manner the pawl actuating pin has capacity to slide within the slot 17 between certain limits.

On the end of the tubular handle 1, as shown in Fig. III, there is a projecting arcuate segment 20 which extends throughout of the circumference of the tool handle. On the sleeve 16 of the tool head, there is a similarly formed arouate segment 22 extending throughout 90 of its circumference. The segments 20 and 22 on the tool handle 1 and tool head 2 respectively serve as stops limiting the relative rotational movement of these elements.

When the parts are in the position shown in Figs. II and III, the pawl actuating pin 12 is urged outward to strike against the cam surface 11 of the pawl 9 in such manner as to cause the tooth 10a to engage the ratchet wheel 4. If, however, the handle 1 be rotated through 180, the limit of rotation established by the stops 20 and 22, the pin 12 which is eccentrically mounted in the shaft 14 will be caused to rotate about the cam surface 110 11 at the same time swinging the pawl 9 to a position in which its tooth 10b strikes the teeth 6 of the ratchet wheel 4. Accordingly, with a half turn of the tool handle 1, the pawl 9 is swung from one position to another to reverse the direction of rotation given to the ratchet wheel 4 by back and forth movement of the handle 1. Incident to the reversal of the position of the double-acting pawl 9, the pawl actuating pin 12 is moved inward in its slot 1'? against the pressure of the spring 18 passing over the central area of the cam surface 11, and then it is projected outwardly again swinging the pawl 9 about its pivot.

To bring the ratchet wrench to a neutral position, a quarter turn is given to the handle 1. This moves the pawl actuating pin from the position shown in Figs. II and III to a position in which the end of the pin will strike the center of the cam surface 11, the pin being pushed rearward into its slot 17. The pawl 9 is thereby swung to a neutral position in which neither tooth 10a nor tooth 10b engages the teeth 6 of the ratchet wheel 4. With the ratchet wrench in a neutral position, the part to which the socket 5 of the ratchet wheel 4 is applied may turn without a corresponding turning movement of the tool handle 1.

From the above description it will be noted that the operator of the ratchet wrench of this invention may perform all of the desired functions without releasing his grip on the tool handle 1. By turning the tool handle 1 in one direction, until the stops 20 and 22 are in engagement, the ratchet wrench when moved back and forth will impart a turning movement in one direction to the part to which it is applied. By turning the tool handle 1 in the opposite direction until the stops 20 and 22 are brought into engagement, the direction of rotation of the part to which the tool is applied may be reversed; and by turning the tool handle 1 to an intermediate point in which the stops 20 and 22 are disposed opposite to each other, the tool may be brought to neutral position.

While I have described one particular example or embodiment of my invention, it will be apparent that various changes may be made in the form of the apparatus herein described and illustrated without departing from the spirit of my invention as defined in the claims hereto annexed.

Having thus described my invention, I claim:

1. A ratchet wrench comprising a head having thereon a socketed ratchet wheel and a doubleacting pivoted pawl having a cam surface and teeth adapted to engage the teeth of said ratchet wheel on'one side or the other, a handle fitted to said head with capacity for rotation about its longitudinal axis relatively to said head, said handle having an eccentric slot in the end thereof, and a pin in said slot spring-urged to engage the cam surface of said pawl.

2. A ratchet wrench comprising a head having thereon a socketed ratchet wheel and a doubleacting pivoted pawl having a cam surface and teeth adapted to engage the teeth of said ratchet wheel on one side or the other, a handle fitted to said head with capacity for rotation about its longitudinal axis relatively to said head, said handle having a diagonal slot in the end thereof, a pin in said slot spring-urged to engage the cam surface of said pawl, and a key at the side of said slot for limiting the extent of movement of said spring pressed pin. 1

ADIN U. KERNS. 

